* Description: Easy to use slideshow plugin. Create SEO optimised responsive slideshows with Nivo Slider, Flex Slider, Coin Slider and Responsive Slides.
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* Version: 2.6.3
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* Author: Matcha Labs
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* Author URI: http://www.matchalabs.com
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* License: GPLv2 or later
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
The return type of return false; (false) is incompatible with the return type documented by MetaSliderPlugin::register_shortcode of type string.
If you return a value from a function or method, it should be a sub-type of the
type that is given by the parent type f.e. an interface, or abstract method.
This is more formally defined by the
Lizkov substitution principle,
and guarantees that classes that depend on the parent type can use any instance
of a child type interchangably. This principle also belongs to the
SOLID principles
for object oriented design.
Our function my_function expects a Post object, and outputs the author
of the post. The base class Post returns a simple string and outputting a
simple string will work just fine. However, the child class BlogPost which
is a sub-type of Post instead decided to return an object, and is
therefore violating the SOLID principles. If a BlogPost were passed to
my_function, PHP would not complain, but ultimately fail when executing the
strtoupper call in its body.
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}
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// lets go
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$this->set_slider($atts['id'], $atts);
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$this->slider->enqueue_scripts();
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return $this->slider->render_public_slides();
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}
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/**
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* Set the current slider
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* @param $id
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* @param array $shortcode_settings
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*/
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public function set_slider($id, $shortcode_settings = array())
<a href="https://twitter.com/share" class="twitter-share-button" data-url="http://www.metaslider.com" data-text="Check out Meta Slider, an easy to use slideshow plugin for WordPress" data-hashtags="metaslider, wordpress, slideshow">Tweet</a>
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<script>!function (d, s, id) {
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var js, fjs = d.getElementsByTagName(s)[0], p = /^http:/.test(d.location) ? 'http' : 'https';
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if (!d.getElementById(id)) {
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js = d.createElement(s);
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js.id = id;
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js.src = p + '://platform.twitter.com/widgets.js';
mambax7 /
extgallery
mambax7
If you return a value from a function or method, it should be a sub-type of the type that is given by the parent type f.e. an interface, or abstract method. This is more formally defined by the Lizkov substitution principle, and guarantees that classes that depend on the parent type can use any instance of a child type interchangably. This principle also belongs to the SOLID principles for object oriented design.
Let’s take a look at an example:
Our function
my_functionexpects aPostobject, and outputs the author of the post. The base classPostreturns a simple string and outputting a simple string will work just fine. However, the child classBlogPostwhich is a sub-type ofPostinstead decided to return anobject, and is therefore violating the SOLID principles. If aBlogPostwere passed tomy_function, PHP would not complain, but ultimately fail when executing thestrtouppercall in its body.